Molding apparatus



l0, 1936. c, pAgK nomme APPARATUS Filed July 13, 1953 s sheets-sham- 1Y. lNvr-:NToR Guides Pqck ATTORNEYS `Nimh 10,1936.

c. PlpcK HOLDING APPARATUS Filed July-1s, 1955 s sheets-sheet 2 lNvENToRChoHeS Pook ATTORN EYS PACK HOLDING APPARATUS l Filed .my 1s, 195s March5 Sheets-snaaiI 3 condition, and it is only further down thecylinder'that the material becomes truly plastic.

One reason for the desirability of articles molded from celluloseacetate is the beautiful color eects which may be obtained with thismaterial.

Some additional objects of my invention center about the mixing orblending of different-colored materials to obtain desired color effects,and are to make possible such mixture of material without requiring akseparate mixing operation, and. further. to make it possible to' varythe proportions or percentages of the different colors usedssweilasthenumberofcolorswhichmaybe handled by the machine. v

To the accomplishment of the foregoing and auch other oblectsas willhereinafter appear, my invention consists in the molding apparatuselements and their relation one tothe other as hereinafter are moreparticularly described in thespecincationandsoughttobedefinedintheclaims. The specification is accompanied by 'drawings in which:

., Fig. 1 is a section taken in elevation through a machine -embodyingfeatures of .my invention; A Fig. 2 is anenlarged section taken in theplane oftheline22ofFig.1;'

Fig.43 is an enlarged detail of the feed mechanism;

F18. 4 is asimilar view of a.modification;

Ii'lg.iiiso.sectiontakenintbeplaneofthc line'l-ioflllg.4:and 4 6 showsthe oil temperature regulating -means of the apparatus. l

Y transfer mechanism designated generally by the letter T. Itwlll beevident that downward movement of plunger P compresses the heatedmaterial in cylinder C and extrudes the same into the diel) until themold impressions therein have been filled. vThe plunger may then beretracted, the die opened, and the molded articles removed therefrom. Inthe meantime and subsequent to retraction of plunger P, a preferablymeasured charge of molding material is transferred by the'mechanism Tfrom hopper H to fcyunder C.

Considering the apparatus in greater detail,

the die D may be of conventional type consisting of a cover half and anejector half, the cover half preferably being secured rigidly to oneside of the machine frame, and the ejector half being movable toward andfrom the cover half by appropriate hydraullc'piston and cylinder mecha'-`nism. IThe details of the die and die opening and closing mechanismform no part of the present invention and need not be described indetail.

The cylinder C comprises a chamber' I2 made of heat treated steel andsuitably mounted between the side walls or frame members Il and fit..The cylinder is provided with heating means here exemplified by a jacketI@r provided withvinlet and outlet pipes 2li and 22 for hot oil.' Theoil is heated in a suitable bath 2l from which it is circulated throughtheA cylinder jacket by s; centrifugal pump 26 driven by a motor 28. The'oil bath is housed in a heat insulating furnace oi' chamber 30" and isheated by appropriate- A heretofore described.

electrical resistance heating elements 32. 'Ihe temperature of the oilis automatically controlled by pyrometric temperature control meansindicated at 34, this means serving to control the heating of resistanceunit 32 in response to changes in temperature applied to the pyrod 38immersed in the o'il bath 24. It will be seen that by maintaining theoil bath at a constant temperature and by continually circulating theoil through the cylinder jacket, the cylinder may itself be kept at aconstant temperature. The preferredtemperature depends to some extentupon the particular grade and mixture of material being molded, but forordinary purposes a temperature of 240 F. is desirable when operatingupon cellulose acetate. The maintenance of a constant uniformtemperature is essential for uniform molding results.

The cylinder C and mold D are interconnected by a relatively elongatedconstricted nozzle M which isattached to and forms a part of the ex.trusion cylinder. This nozzle is preferably provid- 'ed with heatingmeans because the molding ma- -plish this in the relatively largersection of ma"- terial in cylinder C. In the present case nozzle 40 issurrounded by an electrical heating unit 42. this' unit being sodimensioned as to maintain the nozzle at the desired constanttemperature once the machine has been warmed up.' In the speciilc casealready mentioned the unit 42 is de-SSQ signed to keep the nomic at atemperature of 240 F. corresponding to the temperature main'- tained inthe extrusion cylinder. It will be understood, of course, that theelectrical heating means 42 may, if desired, be replaced by an oiljacket heated by oil supplied from the bath'll, as

The uppermost portion of erably jacketed separately from the main bodyof the cylinder, thereby providing a jacket M which is used as a coolingjacket,y this'being supplied with cold water through appropriate pip=ing I6. The chilling of the topmost'zone of the cylinder is desirable inorder to discourage attempt at back-flow of the molding material aroundthe plunger. The arrangement shown permits the uppermost layer ofmaterial to remain in solid condition. and it is onlythe lower portionsof material that are in a fused or molten state. This condition isroughly indicated by the gradatlons in size of the nieces of moldingmaterial shown in the drawings. It will be understood. however, that thematerial need not be fed to the cylinder in the-form of relatively largelumps, but may instead be granular or moreilneiy comminuted.

In actual practice relatively large pieces-fof molding material may befed to the cylinder'because of a desire to produce a variegated coloreffect. For this purpose laminations of differentcolored materialmay be.preliminarily secured together, and the resulting sheet may be diced,thus forming lumps of multiple-colored material. This material may befed alone to the cylinder or may be mixed with a considerable quantity'of j viect in a different-colored background. v

The plunger P consists of a heat treated steel '7b.

cylinder C is prefcylinder 50 mounted upon and moved by a cross head 02which in turn is reciprocated by a piston-rod 54 and piston 56reciprocable in hydraulic cylinder mounted between the frame members i4and I0. The cylinder 50 is supplied with oil under pressure throughpipes 60 and $2, the ilow of oil being regulated by appropriate valvemechanism, not shown, designed to exhaust or open one of the pipes whensupplying the other pipe with high pressure liquid. By movement of thevalve in one direction the plunger may be forced into the'cylinder,while movement of the valve in the opposite direction will causeretraction of the plunger from the cylinder. Y

To prevent excessive abrasion and wear of the plunger and cylinder. andto provide a perfect leak-proof seal between the plunger and cylinderdespite the high molding .pressure employed, I provide the hardenedplunger with a relatively soft metal tip or'cap 64. The molding pressuremay be of the order of 100,000 pounds per square inch. and under thisextremely high pressure the Ycellulose acetate tends to wedge betweenthe plunger and cylinder and may result in serious soft nature of thetip prevents scoring of thecylinder. vWear of the cap is itself notserious because this cap may bereplaced when necessary. 'I'he cap ismade of an appropriate soft metal such as copper, german silver, orother nickel alloy.

The mechanism for replenishing the supply of' molding material incylinder C will next be described. This mechanism comprises a hopper orstorage bin H and transfer mechanism T for delivering small measuredquantities of the molding material from the hopper to the cylinder. Thehopper consists of side walls only, the top being left open to permit asupply of the molding material to be dumped therein, and the bottombeing closed by 'a movable surface consisting of the periphery of a drumor cylinder 10. 'Ihe drum 10 is mounted on a shaft 12 jcurnaled inbearings -14 formed in the side walls I4 and i0 of the machine frame.'Ihe drum is preferably rotated intermittently and uni-directionally inorder to move material from the drum to a chute 10 leading to the upperend oi the cylinder. While the desired movement of the drum may beobtained automatically as will be subsequently described, it ispreferably obtained by manual means here exempliiled by a pull rod orrack bar 10 having a handle 00. As is best shown inFigs. 2 and 3 bf thedrawings the rack bar 18 meshes with a pinion 02 which in turn issecured through'a sleeve 04 to an oscillatable pawl plate 86. This platecarries a pawl 08 pivoted at 90 on plate 06 and normally urged intoengagement with the teeth of ratchet wheel 92 by a spring 94. Ratchetwheel 02 is keyed at 06 to the drum shaft 12. It will thus be evidentthat when rack 10 is pulled outwardly by the machineoperator, the drum10 is rotated counter-clockwise as viewed in Fig. 3, or clockwise asviewed in Fig. l, thereby tending to deliver the bottommost materialfrom the hopper to the chute 10 and thence to the extrusion cylinder.

Upon inward movement of the rackbar 10 the drum remains stationarybecause of the slippage forded between the pawl 00 and ratchet wheel Thehopper is preferably provided with a door |00 located at the bottomleading edge of the hopper and operating when closed to preventdischarge of material therefrom. 'I'he door |00 is pivoted on a shaft|02 extending between and iournaled in the side frame members |4 and l0.

'Ihe door is normally held in closed condition by' a spring |04 thetension of which is applied to an xzn |00 extending upwardly from thedoor shaft The outer extremity of door shaft |02 is provided withappropriate mechanism for opening the door at the beginning Aof thefeeding operation. For this purpose the shaft is provided with an arm|00 actuated by a connecting rod ||0 the lower end of which is slottedat I I2 and supported by sleeve 04, the slot permitting longitudinalmovement of the connecting rod. The connecting rod is further providedwith a cam follower roller H4whichbearsagainstthesmfaceofacam ||0 formedintegrally with pinion 02. As will be apparent from inspection of Fig.3, when the manually operated rack bar 10 is in innermost position. thecam follower roller ||4 is depressed, and door |00 is closed. Whenlrackhar 10 is pulled outwardly the resulting counter-,clockwise rotation ofthe pinion and cam causes a prompt elevation of the cam follower andopening of door |00. Inasmuch'as nearly all of the remaining peripheryof the cam is of uniform large radius,`

the door is held open during the'entire outward or feed movement of therack bar. When the rackbar is restored to its innermost position thedoor is again closed, as shown in Fig. 3.

As so far described the feed of material from the hopper to the cylinderis obtained by manual extreme watchfulness and care on the part of theoperator, for otherwise the supply of material to. the cylinder maycumulatively increase or de,- crease with injurious consequences. Inaccordance with a further feature of the present invention the rack bar1l may be pulled through its entire extent of movement, but the amountof' meshes with a sloping rack bar |24, this rack bar y being slidablein guides |20 secured on the outer1 side of frame member |4. The upperportion of the rack bar is provided with teeth |20 adapted' forengagement by a holding dog |00 pivoted at |02. .'I'ne dog |00 isnormally held in engagement with the rack bar by a spring |04.

The sloping rack bar |24 is normally held in the upward position shownin Figs. 1 and 3 by a spring |00. It is arranged to be moved downwardlyby movement of the plunger P, and for this purpose the cross head 02 isprovided with an arm |00 having an extension |40 which passes through aslot |42 in the frame of the machine. Thearm |40 carries an adjustablescrew stop |44 disposed in alignment with the endl of the sloping rackbar |24.

It will thus be evident that upon downward movement of the plunger thesloping rack bar .10 its down duririgh-trici-v iciding toperation. whenl'offthe?tir-lim which =in turn detimeVV due @to adiiference -in g5'ry'erjure materiel-mure cylinder.

for thisinturn varies :with factors such listhe-y granjuierm'iehesef themeteriarend me nature or ci; irsueizerfempiyeu: sueirvariations are. b'Win11 in? Presimt. PPF- rreeuiiT ed histmed-erm feria eerried by .45sleeve 4v the sloti54-a'ifording' vertical movew mentf 'of thecr'annecti'xigl rod; The connecting rodfcarries'a cam follower'roller|58 which cooperates. with a cam-158 secured to the -sleeve I4 fand't'othe' pawl plate Si; The cam |58 is 50 provided with a lift. |60 solocatedas to engage the"cax n follower I when the rack bar 1l hasbeen'pulled toitsfoutermost position. v

'Ijiieijhopper' H iisV mounted ,between the frame lmembers 14 and-"Whylappropriate 'supporting 55 redet-i"ljszumri m. The from; weu'mief thehopper' may be'provide'd with a sight window lll, "thereby permittingthe operator to tell at a gian e v`the levelfofmolding material remain-"'hoppe. 'Ifhe hopper may be addiprovided with/one ordnorepartitions |12whichare removably inserted-in the hoppen lhese partition preferablyextend downwardly to theperiphery of the feed drum |I. They aresupported by suitable means per- 65 'the' partitionsto be' placed orrelatively -,t'lesi'ed in the hopper. In the present case innerwails'jof the hopper are provided ott'ed'ba'rs |14 the" slots i'n whichare -lilr' partitions -nn and m. with .n im by me mum ing the materielwahr-the eidcrfthefdruncr. :er

tchet rack-bar -is held in` v"p s` iti' `rl byfdogilll; and conse-1'quently-the shroud'HU is'"he1'd'infa iixed posi f tion dependent uponthe stroke of the plungerv `inderafter the plunger-'has been retracted.Com-

pletely from the: cylindenjr- Because. of, the rela-v heffpeeaieni-ef'rnei'shreud, 'ami uns plicity, has been-.made somewhat like;v mechwhenMum; the-Supply 'of nig-'J 'I l tirely -omittedandmne feedfpawl ivthereis a sloping.raclefbar1Ql mehinsfwith having apawl-.Ziimeshingwith a rathetwheel "7208; Ratchet Wheel208:45keyedgatgzlltqjthef.-

ywill be understood that upon downwardmov ment of the rackbar,--correspondingY tqrdowng I ward movement of the' p1unger,'the lpawl i,sf-

od |52.- "The lower 'en'dof the oon-A Vof the rack bar, which :movement,follows =door being pivoted'on a-shaft |01 provided with receivesupport the relatively4 erably. horizontal in order to make possibleopenthis ructindiiler'ent colors or' different.v

of the partitions .wills bevmaintained when feed-g this same proportionvexists-on the surface of the drum. and thexdirectionoffeed-of-thedrum;is, of course, inrrthefsame direction asthe par-eje.; titions in thehopper. u f l -1- f' v The feed movement of -the drum may be lobe tainedmanually'as already described, and

arrangement is desirable because it permits:the operator to feedfmateriahstof-the-extrusion cyl-Q tively substantial time zneededI tochill the 4cellu lose acetate material afterpit vvhascenteredv the mold;the apparatus cannotzibe'used at extrernehyy.4

high speed. There-is consequently ample .-tim e= t v v-i'or the operatortcmanipulateithe feeclghanlley feed ma rial "from thefhopper isproportional ly automaticalbn-.and ,the automatic feed, li b"e;gd

the manual feed already.l .describedmay; preferably isA proportioned:-to .thel .rate of fro, A material by the' machina; r Here again thelrate of usernay be gauged by; the length of the. preceding strokeof theplunger. l k25- directly by thefsloping machbar. Snecma@ pinion 202whichinturn carries apawl vplantel moved backwardly orcounter-clockwise,overthe@n ratchet teeth, but thatupon upward movement;

'the movement of the rack bar is dependent upon the movement of theplunger, the feed is like-r wise dependent upon the precedingmovement ofthe plunger. r 50 The door l .of the hopper may be operated by mechanismsimilar to that already describedrthe an arm In operatedby--aconneetingfrod illy?" slotted at H2 and. carrying a cam follower rollerH4. The cam followery roller engages a camlimg.

corresponding to cam H6 inFig.- 3 but oppositeiydirected and serving toopen the door during the downward and upward movement of the rack bar .Y

200. At the 'end-of thefeed movement, however, ab

mains closed throughout vthe remainder; of thefr molding cycle. z l

A word of explanation .about the angular are? rangement of the press maynot be-amiss. Thal-65 heating and extrusion cylinder is preferably gen.-erailyupright in nature in order to facilitate reftllling the same withadditional molding; rial. The dischargeofextruded material` is; pre

of lthe `path of the plunger. 1 The ..351

arrangement best shown in Flg. l, reconciles these various requirements,for the advantages of an upright cylinder and downward feed areretained, and at the same time the change in direction from the cylinderto the horizontal nozzle is not acute. It will be understood, however,that various-other features of the present invention may be retained'without necessarily employing the angular press arrangement hereinshown.

-It will be noted that therack bar |24 is arranged at a slope parallelto that of the plunger and cylinder, thus permitting the movement of theplunger to be transferred directly to the rack bar. It will also benoted that the use of stop screw I provides an adjustment of the strokeof the rack bar relative to the stroke'of the plunger and may also beused to partially or wholly compensate for lost motion Vof the plungerout of the cylinder, this lost motion being desirable to open thecylinder for the replenishment of molding material.

- n is believed that the construction ondopen ation of my improvedmolding apparatus, as well as the many advantages thereof, will beapparent from the foregoing detailed description. In op eration, the dieis closed and the extrusion plunger is forced downwardly, therebyforcing some of the molten or fused cellulose acetate from the cylinderthrough the nozzle into the die. The material during its passage throughthe vconstrict'ed nozzle is broughtto a uniformly mixed condition anduniform temperatureland plasticity. The temperature of the heatingJacket is maintained constant by automatic temperature control of theoil bath. The plxmger is then .-rotracted and-the die opened to permitremoval o f 'the molded articles. The usual ejector mechanism on the diemay be employed to free the molded article from the die. During the4downward movement of the plunger the feed shroud |20 is moved by thesloping rack bar an amount depending upon the'plunger movement, and thisposition of the shroud is maintained when the plunger is elevatedi' Atany convenient time the operator pulls the feed bar 18 outwardly andthen moves the same inwardly to initial position. During the outwardmovement the feed drum is rtated an amount determined by the position ofthe shroud and proportional to the preceding plunger movement. Uponinitial movement of the rack bar the hopper door I" is opened. At theend ofthe outward movement of the rack bar the holding dog lll ofthesloping rack bar is released, thus permitting the rack bar to moveupwardly to initial position. Upon inward movement of the feed handlethe hopper door is again closed. I'he modified form of the inventionshown in Figs. 4 and 5 bperates generally similarly,` but manualmovement is dispensed with.

My apparatus provides for successful and emcient continuous molding of"articles out of thermoplastics even when relatively difilcult to handle,as in the case of cellulose acetate. The apparatus permits of moldingunder high pressure, yet back-flow of material around the plunger isei'lectually prevented and no destructive wearis conveniently fed to theextrusion cylinder, and the amount of feed is automatically proportionedto the rate of consumption. This is true even when manual feed ispreferred for convenience,

and in such case'the manual movement may be a full stroke not requiringactive attention on the part of the operator for proportioning of theamount of material. The material is heated to a uniform temperature inthe extrusion cylinder, and-in any case is brought to a uniformcondition of mixture, temperature and plasticity in a heatedconstri'cted4 nozzle before entering the mold. The mold may be separated.in a horizontal direction, if preferred, while maintaining theadvantages of a generally upright extrusion cylinder and a substantiallydownwardfeed of molding material. A

It will be apparent that while I have shown and described the apparatusof my invention in preferred forms, many changes and modincations may bemade in the structures disclosed without departing from the spirit ofthe invention, defined in the following claims.

I claim:

1. Apparatus for molding thermoplastic material comprising a die, aheating and extrusion cylinder. a plunger movable into -and out of saidcylinder, a hopper carrying a supply of the moldingmaterial, means totransfer a measured quantity of the material from the hopper to thecylinder, and means to' maintain said transferred quantity of materialconstantly in .proportion to therate of use of materia-1v by theapparatus.

2. Apparatus for molding thermoplastic material comprising a die, aheating and extrusion cylinder, a plunger movable into and out of' saidcylinder, a hopper carrying a supply of the mold-A` ing material, meansto transfer a quantity ofthe material from the hopper tothe cylinder,and means to automatically determine the amount of material transferredto the cylinder in dependence upon the lengths of the strokes of theplunger.

3. Apparatus for molding thermoplastic-ma-l terial comprising a die, aheating and extrusion cylinder, means to heat the cylinder to a constanttemperature, a plunger movable into and out of said cylinder, a' hopperadapted to carry a s up plv of the thermoplastic material, means totransfer a quantity of the material from the hopper to the cylinderafter eachv stroke of the plunger, and means to automatically determinethe amount of material transferred to the cylinder in proportion to theamount of material forced from the`cylinder. in the preceding stroke ofthe plunger.

4. Apparatus for molding thermoplastic material comprising a die, aheating and extrusion cylinder, a plunger adapted to move into and outof the cylinder with a variable length stroke.' a hopper carrying asupply of molding material, a feeding device for delivering moldingmaterial from said hopper to said cylinder includingameasuring device,connections between the measuring device and the plunger for controllingthe quantity of moldable material measured out by the measuring deviceby the stroke of the plunger, and means for guiding the measuredmaterial'to the said cylinder.

. 5. Apparatus for molding thermoplastic material comprising a die, aheating and extrusion 6. Apparatus for molding thermoplastic mate- -riallcomprising a die, a heating and extrusion cylinder, a plunger movableinto and out of said cylinder, a hopper carrying a supply of thethermoplastic materiahmeans tov transfer a measured quantity of thematerial from the hopper tothe cylinder including a drum rotatable atthe bottom of the hopper to deliver material from the hopper, a chutefor guiding the material from the drum to the cylinder, and means torotate the drum an amount proportional to the'stroke of the plungerduring the preceding molding operation.

7. Apparatus for molding thermoplastic material comprising a die, aheating and extrusion cylinder, a plunger adapted to move into and outof the cylinder with a variable length stroke, a hopper carrying asupply of molding material, a feeding device for delivering moldingmaterial from said hopper to said cylinder including -si measuringdevice, connections between the measuring device and the plungerl forcontrolling the quantity of moldable material measured out by themeasuring device by the stroke of the plunger,

Va meansv for guiding the measured material to the said cylinder, and amanually operable de- .vice connected to the feeding ldevice fordeliveringa measured quantityV of moldable material to the guidingmeans.

8. Apparatus for molding thermoplastic material comprising a die, aheating and extrusion cylinder' in ilow communication therewith, aplunger movable into and out 'of the cylinder, means to heat thematerial in the cylinder, a hopper carrying a supply of the moldingmaterial. a feed drum at the bottom of the hopper, manually operatedmeans for rotating the feed drum, and means to automatically limit thefeed movement to an amount dependent upon the rate .of use ofmaterial bythe apparatus.

9. 'Apparatus for molding cellulose acetate comprising a die, aheatingand extrusion cylinder in flow communication therewith. a plungermovable into and out of the cylinder, means to heat the material'in the.cylinder, a hop- 'per carrying a supply of the molding material, a feeddrum at the bottom of the hopper, manually operated means for rotatingthe feed drum, and means automatically operated by the plunger formaking the manually operable means eifective to only a limited extentdependent upon the stroke of the plunger during the preceding moldingoperation.

10. Molding apparatus for molding thermoplastic material comprising adie, a heating and extrusion cylinder in vilow communication with thedie, a plunger movable into the cylinder to force material from thecylinder into the die,

means to heat the cylinder :in order to fuse the.

material therein, and means to cool the open end of the cylinder toprevent back-now around the-plunger.

11. Moldingy apparatus for molding cellulose-Iv acetate comprising adie, a heating and extrusion cylinder in iiow communication with thedie, a.v plunger movable into the cylinder to force 'material from thecylinder into the die, means to heat the cylinder in order to fuse thematerial therein, means to feed solid cellulose acetate to the open endof the cylinder, and means to cool the open end of the cylinder toprevent back-now t around the plunger.

12. Apparatus for molding cellulose acetate'.

comprising a die, a heating and extrusion cylinderv in tlow.communication therewith, a plunger mov` able into and out of thecylinderand adapted to have varying length strokes, means to heat thematerial in the cylinder, a hopper carrying a sup: ply of the moldingmaterial including an opening,"-`

terial comprising a die, a lheating-and lextrusion cylinder in flowcommunicationtherewith, a plunger movable into and out of the cylinder,means to heat the material in the cylinder.' a hopper carrying a'supplyof the molding material',

a feed drum at thc bottom of the-hopper, and

means for automatically transferring from the hopper an amount ofmaterial dependent upon the stroke of the plunger during the precedingmolding operation. inorder to replenish the maf terial in the cylinder.i

14. Apparatus for molding cellulose acetateV comprising a die, a heatingand extrusii'm.stylinL 4der in now communication therewith. a plungermovable into and out of the cylinder, means heat the material in thecylinder, a hopper ing a supply of the molding material, a feeddrum atthe bottom of the hopper, and means for automatically rotating the feeddrum subsequent to the stroke of the plunger an amount xdependent uponthe stroke of the plunger, inorder to plenish the material in thecylinder preparatory to the next molding operation. l e..

15'. An apparatus for molding thermoplasti material comprisinga die, aheating and extmf sion cylinder in4 flow communication therewith'. and aplunger movable into and out of the'cyli'n`- der for forcing materialfrom the cylinder'into the die under high pressure, the end of saidplunger being made of relatively soft metal,

metal being of sumcient softness to be expanded into contact with thecylinder walls when the plunger is brought into contact with material inthe cylinder under high pressure.

16. Apparatus for molding cellulose acetate comprising a die.` a heatingand' extrusion'cylinder in ilow communication therewith, and a plungermovable into and out of the cylinderl for forcing material from thecylinder into the die under high pressure. the end of said plunger beingprovided with a cap made of a material com# prising principally copper,said material being adapted to expand into contact with the cylinderwalls by bringing the plunger into contact with material in the cylinderunder highl pressure.

CHARLES PACK.

- DI SCLAI M E R I 2',033,735.Uharles Pack, Forest Hills, N. Y. MOLDINGAPPARATUS. Y Patent dated f `March 10, 1936. Disclaimer filed February25, 1939, by the assignee,

.Tennessee Eastman Corporation; the patentee, assenting.

' Hereb enters this disclaimer to claim 1 of said Letters Patent.. @amgMarch 28, 1939.]

